Two Destroyers,

One Drydock

The recent dual docking of two U.S. Navy Destroyers took remarkable planning, skill, and extreme precision, and is a discriminating capability BAE Systems provides to the U.S. Navy.

It was a typical day in San Diego, California. The sun was shining and the skies were blue. But the day was anything but normal for our team at the BAE Systems’ shipyard. They were preparing to do something that had never been done in the yard.

Ken Brock was among those who would experience it. He followed his usual routine on that October morning, arriving early to meet with his team for safety and project readiness preparations. But this job wasn’t going to be routine. The BAE Systems San Diego Ship Repair team was about to embark on the simultaneous lifting of two U.S. Navy, 510 foot-long guided-missile destroyers out of the water inside a drydock. The two warships were the USS Stethem (DDG 63) and USS Decatur (DDG 73), each with a displacement of about 9,000 tons.

The docking of the USS Stethem and USS Decatur is the first tandem docking of DDGs since 2012, when BAE Systems collaborated with the Navy to dual dock the USS Mason (DDG 87) and USS Bulkeley (DDG 84) at its Norfolk, Virginia shipyard. Collaboration and capability were key with those two destroyers, and it was no different this time in San Diego.

“This was the first time our San Diego shipyard has docked two large warships ships in one drydock, but it wasn’t a first for the company,” said Brock, a project manager who has worked in the San Diego yard for four decades. “D2, as we call the dual docking, marks a significant milestone for BAE Systems Ship Repair on the West Coast.”

Simultaneously
DockingTwo U.S. Navy Destroyers

Navy’s needs, our capabilities

“The ability to dock two DDGs is a special capability that we bring to our Navy customer and comes at a critical time when additional throughput is necessary to meet surface combatant demands and modernization requirements,” said David M. Thomas, Jr., vice president and general manager of BAE Systems San Diego Ship Repair. “Beyond the remarkable nature of this tandem docking, it is business as usual for our team and partners given our significant experience working with Arleigh-Burke class destroyers.”

The complex work of modernizing and repairing a Navy destroyer is managed through a master schedule to ensure timely completion. BAE Systems’ planning for D2 involved months of coordination with the ship’s crew and two of the Navy’s repair management organizations: Southwest Regional Maintenance Center (SWRMC) in San Diego and Naval Sea Systems Command (NAVSEA) in Washington, D.C. More importantly, the tandem docking is only possible because of the massive dock space that BAE Systems has available in San Diego and the ships’ synchronous repair schedules.

“Drydocking is an extremely detailed-oriented, brilliant process,” said Brad Gibson, BAE Systems’ dockmaster, who directs and oversees all of the docking evolutions at San Diego Ship Repair. “Planning for a dual docking capability like this one required years of engineering masterminding, beginning back in 2015, when the company first decided to invest in the Pride of California drydock. This specific evolution for the Stethem and Decatur took countless hours of preparation between hundreds of people to make it successful. And, it was.”

The drydocking unfolds

BAE Systems’ Pride of California drydock has a lifting capacity of 55,000 tons. It’s 950 feet long, 160 feet wide and became operational in February 2017 as the largest floating dock in San Diego. The entire process of drydocking the Stethem and Decatur took about 18 hours and was the first time the Pride of California had been used for this truly special capability.

Here’s how it worked: The drydock was submerged by flooding the ballast tanks hidden under the floor of the dock and within the side walls. Tug boats and mooring lines maneuvered the ships into place over the submerged dock with extreme accuracy. The ships’ positions and their proximity to the dock floor had to be precise because of the hull shape and dimensions of the sonar dome below the surface of the water. Once divers verified that the ships were properly in place, the drydock’s ballast tanks were pumped dry so that the natural buoyancy of the dock allowed the ships to be slowly raised. The powerful destroyers now sit upright on perfectly engineered blocks, strategically placed on the drydock floor to match each ship’s hull.

SWRMC, the Navy maintenance center, worked with the ships’ crew – which number about 280 sailors each – to prepare the ships to meet stability requirements prior to being lifted out of the water. The restorative work onboard the two vessels began immediately after the ships were high and dry.

“As the prime contractor, we are overseeing the hull preservation, mechanical and engineering repairs aboard both ships in coordination with our customer,” Brock said. “The whole process from planning to execution is a great example of our capability to help ensure the combat readiness of the fleet by providing this kind of D2 operation and capacity at our San Diego shipyard.”

Finishing up

The Stethem and Decatur are scheduled to be simultaneously refloated in April. Work aboard the ships is expected to be completed by October 2020. The ability to drydock two ships at once is a resourceful capability and an efficient way to get ships back out into Navy operations so they and their crews can carry out their important national security mission.

“The double-docking effort by industry and the Navy team is a great example of increasing agility with resources available,” James Geurts, assistant secretary of the Navy for research, development and acquisition, said in a recently published NAVSEA article. “The concept of double docking Stethem and Decatur can pay long-term dividends to our maintenance planning, strategies and execution to get the increased output needed. This docking adds depth to our maintenance capabilities and builds the muscle memory needed to do it again in the future. It’s increasing flexibility within our existing industrial base.”

BAE Systems’ tandem drydocking evolution in San Diego started mid-afternoon on October 8 and culminated with the two ships successfully lifted out of the water the next morning.